Electrochemically Driven α,β-Dehydrogenation of Flavanones, Azaflavanones, and Thioflavanones.

Abstract

α,β-Dehydrogenation of flavanones represents an ideal strategy to synthesize various flavones but remains challenging because of the requirements for rigorous conditions. Herein, a straightforward and efficient route for the synthesis of flavones via electrocatalysis is disclosed. This electro-oxidative approach shows a broad substrate scope, including azaflavanones and thioflavanones, which could be performed in an undivided cell without the removal of air or water and in the absence of metal catalysts, ligands, or external oxidants. Moreover, the combination of cyclic voltammetry, square wave voltammetry experiments, and density functional theory (DFT) calculations revealed the plausible mechanism.